In a conventional window regulator for a vehicle door, a window glass is moved up and down between a closed position where the window glass closes an aperture in the vehicle door and an open position where the window glass is lowered into a compartment formed in the vehicle door. The window glass usually rides or slides in fore and aft glass run channels that are installed in the vehicle door. The window regulator further includes one or more guide rails. Each guide rail has a lifter thereon that holds a lower edge of the window glass. The lifter is moved up and down on the guide rail between an upper position corresponding to the closed position of the window glass and a lower position corresponding to the open position of the window glass. A cable drive assembly is typically provided for driving the one or more lifters upward or downward on the one or more guide rails.
Some vehicles, however, have relatively complex shapes and as a result the guide rails may incorporate some amount of helical twist to guide the movement of the window glass through a complex motion between its closed and open positions. The amount of helical twist incorporated to guide the complex motion, may differ between a first guide rail positioned towards a front edge of the window glass, and a second guide rail positioned towards a rear edge of the window glass.
Providing a plurality of individually formed guide rails can increase the cost of the window regulator however. It would be advantageous to provide a way to provide a window regulator that addresses the issue of cost.